Machine tool transmission and control therefor



March 21, 1950 c. M. MIROSSAY 2,501,236

MACHINE TOOL TRANSMISSION AND CONTROL THEREFOR Filed June 4, 1947 9 Sheets-Sheet 1 l ll 5 a;

- INVENTOR. EHRYSHNTH M. Mmussay March 21,' 1950 c. M. MIROSAY 2,501,286

mcunm TOOL mmsmssxon 1minv coumor. THEREFOR Filed June 4, 1947 9 Sheets-Sheet 2 HTTCIHNEYS I INVENTOR. EHRysHNTH M. Mmussay BY March 21, 1950 c. M. MIROSSAY 2,501,236

mam-11m: TOOL TRANSMISSION AND CONTROL THEREFOR Filed June 4, 1947 9 Sheets-Sheet 5 INVENTOR. 'EHRISFINTH MMmussny BY W WZM ZZM m,

HTTDRNEYS March 21, 1950 c. M. MIROSSAY MACHINE TOOL TRANSMISSION AND CONTROL THEREFOR 9 Sheets-Sheet 4 Filed June 4, 1947 INVENTOR. EHRysHNrH M. Mmussny BY wfi yflm 93mm HTTDR'NE 5 March 21, 1950 c. M. MIROSSAY MACHINE TOOL TRANSMISSION AND CONTROL THEREFOR Filed June 4, 1947 9 Sheets-Sheet 5 l rm w j WE llll II h-- P MT nMvM w-/ mz -2 MN- l flNUm E 8W4. QQNAI- NON QZ 3 1 fi vt 3F mmq m 1'; BUN N O INVENTOR. E HRISFINTH M.M|RU55H] By fi m?! a RN. 5'

Margh 21, 1950 c. M. MIROSSAY 2,501,286

MACHINE TOOL TRANSMISSION AND comm. 'l'I-lEREFOR Filed June 4, 1947 9 Sheets-Sheet 6 &m

INVENTOR.

E l- LEYSHNTH MMmnssHy mz fiv 39mm Hwunuays 93% HTT R'NE s 9 Sheets-Sheet 7 V INVHVTOR. BHR'YSFINTH M. MIRDSSFIY C. M. MIROSSAY MACHINE TOOL TRANSMISSION AND CONTROL THEREFOR March 21, 1950 Flled June 4, 1947 March 21,- 1950 c. M. lvnRossAY MACHINE TOOL TRANSMISSION AND CONTROL THEREFOR Filed June 4, 1947 9 Sheets-Sheet 8 llllrlllllalllll lllull-Inll ium INVENTOR. EHRYSHNTH M. MIRDSEH} HITDRNE 5 March 21, 1950 c. M. MIROSSAY 2,501,286

MACHINE TOOL TRANSMISSION AND CONTROL THEREFOR Filed June 4, 1947 9 Sheets-Sheet 9 I 1 I: 88 'l 154 E ,/I I l i E 247.. v 99 E 5- 24 I! y en /,7' 78 I l: 88 \xa ll as; C 97 v II 93 24)? ee -0 77 9 INVENTOR. EH RISFINTH MMmussnY H-rmm lays 1 I} Patented Mar. 21, 1950 MACHINE TOOL TRANSMISSION AND CONTROL THEREFOR Chrysanth M. Mirossay, South Euclid, Ohio, as-

signor to The Warner & S Cleveland, Ohio, a corporation of Ohio wasey Company,

. Application June 4, 1947, Serial No. 752,353 23 Claims. (01. 192-4) This invention relates to a machine tool and particularly to an improved mechanism for controlling the speeds, direction of rotation and the starting and stopping of a movable part of a machine tool such as the work spindle.

An object of the invention is to increase the efliciency of a machine tool as, for instance, a lathe, by enabling the operator to effect with a minimum of efiort and skill on his part the changes in speed, direction of rotation and the starting and stopping of a movable part of the machine tool as. for instance, the work spindle.

A more specific object is to increase the chiciency of a machine tool, such as a lathe, by enabling the operator to effect with a minimum of attention and skill on his part the starting and stopping of the work spindle in the headstock,

manually controlled member can be moved in acertain plane to control the direction of operation of the change speed transmission, the starting and stopping of said transmission and the the direction of rotation of said spindle, and the shifting of the gears of the change speed transmission in the headstock to vary the speed of rotation of the spindle.

Another object of the invention is to accomplish the objects above enumerated in such a way as to reduce the wear and tear on the-change speed transmission and thus increase the life of the machine and keep maintenance costs tov a minimum.

Another objectof the invention is to provide in a machine tool of the type having a movable part, a change speed transmission for moving said part at different speeds in opposite directions and means for selecting or preselecting the speed of said part for the: different operative steps of a work cycle; improved and novel means for attaining the selected or preselected speed of said part and which means automatically effects a complete speed changing cycle of operation after the operator has manually initiated said cycle of operation.

Another object of the invention is to attain the above mentioned objects by means of an improved and novel pressure fluid operated mechanism for effecting the automatic cycle of the speed changing operation.

Another and more detailed object of the invention is to provide a pressure fluid operated mechanism, as referred to in the last object, and wherein the automatic cycle of operation includes the disengagement of a main drive clutch,

the initiatic of a slow speed non-working drive to the transmission to facilitate the shifting of the shiftable elements, a shifting of said elements in a predetermined way and the reengagement of the main drive clutch.

Another object is to provide a fluid pressure application of a brake means, and in another plane transverse to the first plane to initiate the non-working drive to the transmission and the automatic cycle of'the speed changing operation.

Another object is to provide in a machine tool means for shifting the shiftable elements of a change speed transmission wherein once the shifting cycle has been initiated the completion of said cycle is automatically attained independently of any effort or attention of the operator and without the clashing of the shifta/ble elements.

Another object is to provide in a machine tool having a change speed transmission improved mechanism for shifting the shiftable elements of said transmission so that the time required to change from one speed to another is uniform throughout the entire speed range of the transmission.

A further object is to provide a pressure fluid operated mechanism, as previously referred to, and wherein the automatic cycle of operation includes the disengagement of a main drive clutch, the initiation of a slow non-working drive to the transmission to facilitate the shifting of the shiftable elements, then after a predetermined time delay a shifting of said elements in a selected or preselected way, and the reengagement of the main drive clutch.

Further and additional objects and advantages of the invention not hereinbefore referred to will become apparent hereinafter during the detailed description of an embodiment of the invention illustrated in the accompanying drawings, wherein Fig. 1 is a front elevational view of a turret lathe to which the invention has been applied for purposes of illustration.

Fig. 2 is a developed view of a. portion of the change speed transmission in the headstock and which forms the drive to the work spindle.

Fig. 3 is a developed view of the remainder of the change speed transmission in the headstock of that shown in Fig. 2 and forming the drive to the work spindle.

Fig. 4 is a fragmentary view, partly elevational and partly sectional, of the main control lever on the front of the headstock of the turret lathe shown in Fig. 1 and of certain of the control 3 valves of the fluid pressure circuit, said view being on a larger scale than Fig. 1.

Fig. 5 is a sectional view taken substantially on line 5-5 of Fig. 4 looking in the direction of the arrows, and shows by full lines the control handle in its intermediate position.

Fig. 6 is a sectional view taken substantially on line 6-5 of Fig. 5 looking in the direction of the arrows.

Fig. '7 is a sectional view taken substantially on line 1-1 of Fig. 5 looking in the direction of the arrows.

Fig. 8 is a sectional view taken on line 8-8 of Fig. 4 looking in the direction of the arrows, of the valve shown at the top of Fig. 4, the section of Fig. 8 being taken in a substantially horizontal plane.

Fig. 9 is a fragmentary plan view of the headstock on a larger scale and with the speed selector or preselector valve shown in section.

Figs. 10, 11, 12, 13, 14 and 15 are sectional views through the speed selector or preselector valve and are taken, respectively, on line I -H}, "-1 I, 12-", l3-l3, I4-l4 and l5-I5 MM. 9 looking in the direction of the arrows.

Figs. 10a, 12a and 13a are developed views of circumferential portions of the valves shown in Fig. 9 and located intermediate the sections of Figs. 10 to 15 inclusive and showing particularly the inlet and exhaust passageways. i

Fig. 16 is a view of the headstock partly in end elevation and with certain parts broken away and shown in section, the sectional view being taken substantially on line i5-l5 of Fig. 9 looking in the direction of the arrows.

Fig. 1'7 is a sectional view taken substantially on line l'I-ll' of Fig. 9 looking in the direction of the arrows.

Figs. 18 and 18a (sheets '7 and 8) together constitute a diagrammatic showing of the fluid pressure circuit in the headstock with the control handle in its most inward position, i. e., its cycle initiating position.

Fig. 19 (sheet 7) is a sectional view located within Fig. 18 and is taken substantially on line lS-l! of Fig. 18 looking in the direction of the arrows.

Fig. 20 (sheet 1) is a fragmentary end elevational view partly in section of the selector valve housing and the casting for the gear shifting motors, said section being taken along line 20-20 of Fig. 18a.

Fig. 21 (sheet 1) is an enlarged fragmentary view of the time delay unit associated with the valve shown at the top of Fig. 4.

Fig. 22 (sheet 1) is a cross section through one of the plates of the time delay unit shown in Fig. 21.

Figs. 23, 24 and 25 (sheet 9) are enlarged sectional views of the gear shifting mechanisms and the fluid pressure motors for actuating the same shown in different operative positions, and

Fig. 26 (sheet 1) is a fragmentary sectional view similar to a portion of Fig. 5, but showing the control lever in its most-outward position.

In Fig. 1 there is shown a turret lathe comprising a bed 30 at one end of which is located the headstock 3|. A work spindle 32 is rotatably mounted in the headstock to be driven at a plurality of different speeds and in opposite directions by means of change speed gearing which will now be described.

Referring to Fig. 2 wherein a portion of. the change speed gearing is illustrated, it will be seen that a power source, in this instance a 4 sheave 33, is secured to the main drive shaft 34 and said sheave can be driven in any suitable manner. A fluid pressure operated friction clutch is mounted on the shaft 34 and comprises a sleeve-like clutch member 35 keyed to the shaft and carrying in a well known manner a series of clutch plates 36. The member 35 has flxed thereto a housing 31 in which is movably mounted a clutch actuator or piston 38. A stationary ring 39 surrounds a portion of the sleeve 35 and said ring is provided with an annular groove 40 which is always in communication with an opening 4i in the sleeve 35. A supply conduit 42 (later to be referred to) is connected to the stationary ring 39 and is in communication with the annular groove 40 and hence the opening 41. The opening 4| in the sleeve 35 communicates with an axially extending duct 43 formed in the shaft 34 and said duct in turn communicates with an opening 44 in the sleeve 35 which terminates within the housing 31 and to one side of the piston or actuator, wherefore the actuator or piston 38 can be subjected to pressure fluid to move the same in a clutch actuating direction.

A clutch element 45 is freely rotatable on the shaft 34 adjacent the right hand end of the sleeve 35 and is provided with an enlarged housing portion which internally carries a series of clutch plates 46 interposed between the plates 36 carried by the clutch member 35. It will be understood that when the piston 38 is moved by the pressure fluid toward the right the clutch plates 36 and 46 will be pressed together or engaged and hence the clutch element 45 will be driven by the shaft 34 and element 35. The clutch element 45 is provided with a hub portion having thereon a gear 41 which imparts forward rotation to the change speed transmission. as will later be explained.

In order to impart to the change speed transmission and the work spindle a reverse rotation, a slow non-working rotation in the forward direction and a braking action thereto, a planetary gear unit now to be described is operatively associated with the drive shaft 34. This planetary unit functions to impart the reverse rotation, the slow-non-working forward rotation and the braking action to the transmission independently of the main forward clutch previously described. The planetary unit may be housed in the headstock or in a separate casting secured to the headstock as will be well understood in the art.

The drive shaft 34 is extended beyond the main forward drive clutch mechanism hereinbefore described, 1. e., to the right thereof as viewed in Fig. 2, and the extended portion of the shaft has fixed thereto a sun gear 48. The sun gear 48 during the operation of the machine rotates constantly with the shaft 34 in a forward direction and constitutes the driving member of the planetary gear unit. The unit also includes internal gears 49 and 50 spaced axially of the shaft 34 and provided with hub portions 5i and 52, respectively, freely rotatable on the shaft and rotatable within suitable bearing supports formed in the headstock or in the separate casting as the case might be.

A planet gear carrier 53 is freely rotatable on the shaft 34 intermediate the hub portions 5| and 52 and internally of the internal gears 49 and 50. The gear 50 is slightly larger than the gear 49, as for instance, two teeth larger. The gear carrier 53 is formed,-in this instance, of two separate parts bolted or otherwise secured together. The carrier mounts one or more bearing shafts 44 extending parallel to the main shaft 34 and each provided with an elongated pinion 55 which meshes with the internal gears 49 and 59 and also with the gear 48. One part of the planet gear carrier 53 is provided with an integral extension passing between the internal gears 49 and 59 and externally surrounding the internal gear 49 and constituting a brake drum 56. The external circumference of the hub portion 5| of the internal gear 49 also constitutes a brake drum as does the external circumference of the internal gear 50. That is, the unit includes three brake drums with the drum 56 connected to the planet gear carrier 53 and the other two drums constituting parts of the internal gears 49 and 50.

Brake bands 51, 58 and 59 of the external contracting type surround the hub portion 5| of the internal gear 49, the brake drum 56 of the planet gear carrier 53 and the external circumference of the internal gear 50.

The brake bands 51, 58 and 59 comprise brake lining material and metal strips supporting the same with the free ends of the strips bent around and secured to pins 60, see Fig. 18. The left hand pins 60, as shown in Fig. 18 (sheet '7), are secured to the headstock or casting while the right hand pins 60 abut, respectively; the piston rods of three fluid pressure motors later to be referred to.

It will be seen that the brake bands float but are held against axial displacement relative to their drums and surround their respective drums and can be contracted into engagement with said drums upon proper movement of the pistons of said fluid pressure motors. The fluid pressure motors for the brake bands 51, 58 and 59 are indicated in Fig. 18 at 6|, 62 and 63 respectively.

Each of the fluid pressure motors 6|, 62 and 63 comprises a cylinder in wh ch is movably mounted a piston that carries the piston rod. These cylinders are formed in the headstock or in the separate castings supporting the unit and one end of the cylinders is in communication with pressure fluid conduits, later to bereferred to, wherefore it will be understood that when pressure fluid is admitted to a cylinder through the referred to conduit its piston will be moved in a direction to contract. the brake band operatively associated therewith. The contraction of the brake band 51 ho ds the hub 5i against rotation and, as will later be explained, imparts a braking act on to the transmission. The contraction of the brake band 58 holds the planet gear carrier 53 against rotation, wherefore the pinion 55 is rotated by the gear 48 in the reverse direction and imparts to the internal gear 49 a similar reverse rotation and in turn there is imparted to the transmission a reversed ro ation. When the brake drum 59 is contracted the internal. gear 50 is held against rotation, wherefore the pinion carrier and its p nion or pinions 55 as a unit rotate around said internal gear 50 and a slow non-working rotation is imparted to the internal gear 49 in a forward direction due to having a less number of teeth and which rotation in turn is imparted to the transmission as a slow non-working rotation of the latter to facilitate the shifting of the gear cones.

The hub portion 5! of the internal gear 49 is provided with a gear 64 which with the gear 41 on the clutch member 45 previously described functions to impart to the transmission reverse or forward rotation as the case may be. The gear 64 is larger than the gear 41, and although the gear 64 is driven through the planetary gearing in a reverse direction at a slower rate than.

6 the forward rate of the gear 41. said gear 94. due to its large size, will impart to the transmission a rate of speed in the reverse direction substantially equal to its forward speed.

5 A three gear cluster is rotatable on a countershaft 65 mounted in the headstock but is held against axial movement on said shaft. This three gear cluster comprises a gear 66 constantly in mesh with the gear 4! and a gear 61 constantly in in mesh with thegear 64 and in addition an intermediate gear 68. The gears 61 and 68 of the cluster may be intermeshed, respectively, with the ear 69 or the gear III of a shiftable two-step gear cone mounted on the rotatable spline shaft H located in the headstock, wherefore it will be seen that said spline shaft can be driven from the drive shaft 34 in both the forward and reverse directions at either one of two different speeds. The spline shaft II also carries a second shiftable two-step gear cone formed of the gears 12 and 13 which can be selectively intermeshed, respectively, with gears 14 and I5 fixed on a rotatable shaft 16 mounted in the headstock. The shaft 16 has fixed thereto an elongated gear 11 which meshes with the largest gear 18 of a shiftable three-step gear cone in two positions of said cone. This three-step gear cone is mounted on the spline shaft I9 that is located in the headstock and said three-step gear cone includes the gears 80 and 8| in addition to the gear 18.

Referring to Fig. 3, the three-step gear cone just referred to is shown in full lines in a position wherein the gear 18 is meshed with the elongated gear 11 while the gear BI is in mesh with the gear 82 fixed to the work spindle 33. In Fig. 3 in the intermediate dash line position of the three-step gear cone the gear'18 is'still in mesh with the elongated gear Ti and also is in mesh with the gear 83 of a two gear cluster fixed on the work spindle, the other gear of said cluster being the gear 84. At this time the gear 8| of the gear cone is out of mesh with the gear 82 and the gear 80 is out of mesh with the gear 15.

In Fig. 3 the three step gear cone in the most left hand dot and dash line position has been shifted to move the gear 18 out of mesh with the elongated gear 11 on the shaft 16 and into mesh with gear 84 on the work spindle, while the gear 80 of the gear cone is now intermeshed with the gear on the shaft 16 and hence the drive from the latter to the work spindle is through the gears 15, 80, i8 and 84.

From the foregoing description of the trans- 55 mission it will be seen that the work spindle can b driven in both the forward and the reverse direct ons at any one of twelve different speeds depending upon the shifted positions of the two two-step gear cones and of the three-step gear 60 cone.

The two-step gear cone formed of the gears 69 and I9 is shifted by means of a fork straddling the gear cone and carried by a hub portion 85 of the fork which is fixed to a piston rod 86 65 slidable in the headstock (see Fig. 18a sheet 8). The two-step gear cone formed of the gears I2 and I3 isshifted by means of a fork straddling the gear13 and formed on a hub portion 81 that is fixed to a piston rod 88 mounted in the head- 70 stock. The three-step gear cone formed of the gears 18, 80 and M is shifted to its three operative positions by means of a pivoted shoe fitting the groove 89 in the three-step gear; cone and carried by the end of a rockable arm 96 the 0pposite end of which is pivoted within'the head- 7 stock for limited endwise movement as indicated at 9!. The arm 90 Intermediate its ends is pivotally secured as indicated at 92 to a piston rod 93 mounted in the headstock.

The piston rods 85, 08 and 93 are extended from three pressure fluid motors indicated in Fig. 18a at 94, 95 and 95 respectively. Said motors are provided with pistons 91, 90 and 89 secured on the rods 86, 88 and 93 and slidable within the cylinders of the motors.

The operation of the three pressure fluid motors just referred to is controlled by a speed selector valve I mounted in the headstock, see Figs. 9, i6 and 18a. The speed selector valve comprises a valve housing in which the valve body IOI rotates. The valve body IOI has a shaft I02 extending outwardly of the valve housing and coupled to a shaft I03 rotatably carried by the upper part of the headstock and extending beyond the front thereof where it is provided with a hand wheel I00. It will thus be seen that rotation of the hand wheel I04 will cause rotation of the valve body IOI of the speed selector valve. The particular arrangement of the ports and passages in the speed selector valve will be referred to in detail hereinafter.

The shaft I02 has fixed thereto a disc I05 provided on its periphery with twelve detent notches corresponding to the twelve speeds of the spindle and cooperating with said disc is a roller carried at the lower end of a pivoted arm I06 that is urged by a spring-pressed plunger I01 toward the circumference of the disc (see Fig. l7).- Thus the valve body of the speed selector valve will be held in any one of its twelve selected positions. The shaft I03 has fixed to it adjacent its forward end a bevel gear I08 which meshes with a bevel sear I09 fixed to the lower end of an indicator shaft IIO that extends into an indicator carried by the headstock and showing spindle speeds in relation to cutting speeds in feet per minute for diiferent diameters of work and correlated to the selected positions of the valve I00.

The upper part of the headstock also supports a time delay valve III, the housing of which is provided with a valv chamber slidably mounting a valve body 2 and also having at one end of the chamber a time delay unit II3 (see Figs. 4, 8, 18, 21 and 22). The delay unit H3 is inserted into the housing of the time delay valve III from one end thereof and comprises a cup II4 containing a series of baffle disks I I5 carried on a rod extending therethrough and with said disks having peripheral notches staggered with respect to each other and providing tortuous paths through the device for the pressure fluid, wherefore it will take a predetermined time period for the pressure fluid to flow through the unit and into the adjacent end of the chamber of the time delay valve.

A main control valve H6 is carried by a plate III that is bolted or otherwise secured to the front of the headstock with the housing of the main control valve H6 extending through an opening in the front wall of the headstock. The main control valve is provided in its housing with a valve chamber in which is rockably mounted a valve body II 8 and said body in turn is provided with a valve chamber in which a gear shifting cycle control valve body I I9 is slidable.

The rockable valve body H8 is provided with a hub-like portion IIBa that extends outwardly of the valve housing through and beyond an opening in the plate III and is rockably supported in 8 said opening. The slidable cycle valve body H0 is provided with an extension Ilsa which passes through the hub portion IIBa of the rockable valve body H8 and extends beyond said hub portion.

Keyed to the reduced outer end of the hub portion II8a of the rockable valve body H8 is a handle bracket I20 which has two downwardly extending spaced leg portions I20a each provided with a forwardly extending lug I20b (see Fig. 6). The bracket I20 is provided on its upper side with an upwardly extending lug I200.

A stop plate I2I is bolted or otherwise secured to the front side of the plate II! and is provided with downwardly extending stop lugs I2Ia lying on opposite sides and in the path of the stop lug I200 and defining the maximum rocking movement in opposite directions which can be imparted to the bracket I20 and the rockable valve body H0. The plate I2I midway of its ends and adjacent its upper edge is provided with a forwardly extending stop lug I2Ib, the purpose of which will later be explained.

A handle body I22 is pivotally connected to the forwardly extending lugs I20b of the bracket I20, wherefore said handle body can be rocked inwardly and outwardly relative to the front face of the plate III. The handle body carries at its upper end a handle I23 and said handle and said handle body hereinafter will be referred to conjointly as the handle.

The handle is provided below its pivot with a spring-pressed plunger I24 which cooperates with the lower end of the handle bracket I20 and functions to normally maintain the handle in the position indicated in Figs. 5 and 18 as position I. When the handle is rocked inwardly to position III in Fig. 18 the plunger is out of contact with the handle bracket I20 and when the handle is rocked to position II, i. e., its most outward position as shown in Fig. 26, the plunger I24 is compressed and functions when the handle is released to restore the handle to position I. The handle above its pivot is provided with an abutment pin I25 which is aligned with the extension II9a of the slidable gear shifting cycle control valve body II9 when the handle is in position I and which acts when the handle is moved from position I to position III to move said slidable valve body inwardly. It will be pointed out later that the pressure fluid acts on the slidable valve body at the end of the gear shifting cycle to move said body outwardly and thus move the handle from position III to its normal position I.

The handle is provided with spaced stop lugs I22a which lie on opposite sides of the forwardly extending stop lug I2Ib when the handle is in positions I and III. The lugs I22a are so spaced that when the handle is in positions I and III it can only be rocked laterally a limited amount, that is, it can only be rocked to and from clutched disengaged or neutral position to brake position indicated in Fig. 4 as positions N and B. It will be noted that when the handle is in position I or position III it cannot be rocked laterally to forward position F or reverse position R as the stop lugs I22a are in the path of movement of the forwardly extending lug I2Ib. However, when the handle is rocked outwardly to position II then the lugs I22a will not engage the lug I 2Ib and the handle can be rocked laterally its maximum amount within the limits of the lugs I2 Ia, that is, can be rocked to position F or position R. The purpose of rocking the handle inwardly and outwardly from position I to positions III or II and line pressure.

'aeomee 9 laterally from pomtion N to positions F, B or R will become apparent hereinafter.

A spring point I26 carried by the rockable valve body I I6 cooperates with spaced notches in the extension I I9a of the slidable cycle valve body II9 to hold said valve body in its two shifted positions corresponding to handle positions I and .111. The handle bracket I20 is provided with a spring-pressed ball detent I21 which cooperates with a series of recesses formed in the plate II1 to hold the handle bracket I26 in its various laterally rocked positions corresponding to positions F, N, B and R of the handle (Fig. 4).

The hydraulic circuit in which the various valves and fluid pressure motors hereinbefore referred to are included will now be described with particular reference to Figs. 9, 10 to 15 inclusive, 10a, 12a, 13a, 18 and 18a. A pump I28 has its input side connected by a conduit I29 with a diagrammatically shown sump or reservoir I30 (the lower portion of the headstock casting) while its output side is connected with a conduit I3I that extends to a passage or milled groove I32 which is shown in Fig. 4 as located on the inner side of the plate II1 although in Fig. 18 for purposes of convenience as to space said passage is shown on the rear side of the headstock wall. The conduit I3I may contain a suitable pressure relief valve I28a to maintain a predetermined The groove I32 is connected by an inlet groove I33 with the valve chamber of the main control valve H6. The groove I32 is also connected to a pipe I34 which extends to the time delay valve III and is the inlet conduit for said valve. The plate H1 is provided with another groove I35 and a groove or passage I36 extends from said groove to the main control valve H6. A pipe I31 extends from the groove I35 to the time delay valve I I I. In addition, a pipe I38 extends from the groove I35 to the fluid pressure motor 63 which effects the crawl or non-working speed for the transmission. The ,plate H1 is,

provided .with a groove I39 interconnecting a oove I40 that extends to the main control valve and a pipe I that extends to the fluid pressure motor 6| for actuating the brake. The plate H1 is also provided witha groove I42 which interconnects a groove or passage I43 extending to the main control valve I I6 and a pipe I44 extending to the fluid pressure motor 62 for efiecting the reverse drive of the transmission.

The plate I I1 is also provided with a groove I45 which interconnects a groove I46 extendingto the main control valve H6 and a pipe I41 extending to and connected with the supply line 42 for the main clutch. In addition the plate I11 is provided with a groove I48 that interconnects a passage. I49 which extends to the main control valve and a pipe I50 which extends to the time delay valve.

The time delay valve is connected by a pipe II with the speed selector valve I00. This speed selector valve is connected with the time delay valve additionally by a pipe I52. The fluid pressure motor 94 which functions to shift the twostep gear cone formed of the gears 69 and is connected to the speed selector valve by passages indicated diagrammatically at I53 and I54. The fluid pressure motor 95 which actuates the shifting of the two-step gear cone formed of the gears 12 and 13 is connected to the speed selector valve by passages indicated diagrammatically at I55 and I56. In addition, the speed selector valve is connected to a passage in the housing of the motor 95 by a passage indicated diagrammatically at I51. The pressure fluid motor 96 which furlotions to shift the three-step gear cone is connected to the speed selector valve by passages I58, I59, I60, I6I and I62, the flow of fluid in said passages I6I and I62 being controlled by all three pressure fluid motors. The motor 96 is also connected by a pipe I63 with the time delay valve III. In the diagrammatic showing of the passages I53, I54, I55, I56, I51, I58, I59, I60, I6I and I62 in Fig. 18a said passages have been indicated in their entireties by dash lines but will later be described as to their constituent parts and separate reference characters used for this purpose.

The time delay valve III is connected by a pipe I64 with the control valve II6 for the purpose of draining the pressure fluid from the time delay valve in order that said valve can be restored to its normal position as will later be described and as is indicated in Fig. 4. The rotary valve body H8 01 the main direction and drive control valve is provided adjacent its left hand end, as viewed in Fig. 18, with three annular grooves I65, I66 and I61, with said grooves I66 and I 61 connected, respectively, to the grooves or passages I36 and I33. The annular groove I65 is in communication with the central chamber in the rotary valve body by means of a radial port I68 and is also in communication with a drain passage I69. The grooves I66 and I61 are in communication with said central chamber by means of radial ports I10 and I".

The rotary valve body II8 to the right of the annular groove I61, as viewed in Fig- 18, is provided with diametrically aligned radial passages I12 and I13 which communicate with the central chamber, with the passage I12 communicating when the valve body is in neutral position with a drain passage I14 formed in the valve housing as clearly shown in Fig. 19.

When the valve body H8 is rocked to forward position, i. e., to the left of neutral, the passage I12 is in communicationwith the groove or passage I46. When the valve body H8 is rocked to the right of neutral position and intobrake position then the passage I12 is dead-ended, while the passage I13 is in communication with the passage I40. When the valve body 8 is rocked still farther to the right of neutral and into reverse position the passage I13 is deadended and the passage I12 is in communication with passage I43. The rotary valve body II 8 is provided with three axially extending but wide grooves in its circumference which act as drain grooves to place the passages I46, I43 or I40 in communication with the circular drain groove I14a in the valve body II8 connecting with drain passage I14b in the valve housing. The drain pipe I64 from the time delay valve I II communicates with a diametral passage I15 extending through the valve body H8 and communicating with the drain passage I15a in the valve housing.

The slidable gear shifting cycle control valve body H9 is provided with spaced lands I16 and I11 which cooperate in the two different valve body positions with the ports I10, HI and I68. The valve body H9 is further provided with a wide land I 18 and a narrow land I19 located adjacent the right hand end of the valve as viewed in Fig. 18. When the shiftable valve body H9 is in its normal position, as shown in Fig. 5, the land I16 is at the extreme left hand endof the chamber in the rotary valve body H8 and the space between the lands I16 and I11 is in 11 communication with the ports I68 and I10. At this time the land I11 lies intermediate the ports I and I'll and hence the latter port is in communication with the space between the lands I11 and I18 and radial passages I12 and I13. Also at this time the wide land I18 is located intermediate the radial passages I12 and I13 01 the rotary valve body and the diametrical passage I15 therein, and hence said diametrical passage is uninterrupted so that pressure fluid can flow therethrough to drain through passage l15a passing between the wide land I18 and the right hand narrow land I19. When the shiftable valve body II9 has been moved to its most inward position by the movement or the handle to position III as shown in Fig. 18, then the lands I16 and I11 lie on opposite sides of the ports I10 and HI and said ports are in communication with each other. At this time the land I11 interrupts communication between the port HI and the radial passages I12 and I13, while the wide land I18 interrupts the diametrical passage I15 through the rotary valve body II8.

It will be noted that the groove or passage I49 communicates with the right hand end of the valve chamber in the rotary valve body H8 and hence when pressure fluid is admitted to said chamber through this passage it will act to shift the slidable valve body 9 from its most inward or right hand position 01' Fig. 18 back to its normal most left hand position of Fig. 5 and, in turn, shift the handle I23 from position III to position I.

The pipe I31 connects with a port I80 in the housing of the time delay valve II I and said port, in turn, communicates with one end of the time delay unit H3. The interior of the housing of the time delay valve and adjacent the opposite end of the time delay unit is provided with a port I8I which communicates with the drain pipe I64 that extends to the main control valve.

The valve chamber in the time delay valve III and to the right of the time delay unit H3 has siidably mounted therein the time delay valve body H2 and said body is provided with three lands I82, I83 and I84. The valve body II2 to the right of the land I84, as viewed in Figs. 4 and 18, is of reduced diameter as compared to the diameter of the land I82 for a purpose which will later be explained.

The pipe I34 communicates with a passage I85 in the housing of the time delay valve and said passage extends to the right hand and of the valve chamber. The pipe I50 extends to and communicates with a port I86 formed in the valve housing and which communicates with an annular groove I860 formed in the wall of the valve chamber of the time delay valve and located when the time delay valve is in the normal position of Fig. 4 intermediate the lands I83 and I84.

The pipe I34 and passage I86 are connected by a passage I81 with a port I88 in the valve housing which communicates with the valve chamber. The valve housing is also provided with a port I89 which is a drain port as will later be explained. The pipes I5I and I521 are connected, respectively, with radial ports I90 and I 9I communicating directly with the valve chamber, while pipe I63 is connected with port I92 communicating with the circular groove IBM.

The selector valve I00 is carried by a plate I 93 which overlies the fluid pressure motors 94, 95 and 96 and hence the valve housing, said plate and the housings of the fluid pressure motors can be provided with grooves, passages, drilled openings and the like forming short passages for the pressure fluid (heretofore indicated and identified diagrammatically) and without requiring the use of piping for such purpose, as clearly shown in Figs. 9, 10 to 15 inclusive, 17 and 18a.

The rotatable body IOI of the speed selector valve is provided with a bore I94 that extends part way through the body from the rear end thereof. The valve body is provided throughout its length with a plurality of circularly spaced radial ports connecting with the bore I94 and with a plurality of cylindrical recesses 0r grooves having axially extending branch grooves in the periphery of the valve body (see Figs. 10a, 12a and 13a). It will be understood that the valve body IOI has twelve different operative positions since there are twelve operative speeds for the spindle.

In Figs. 10 to 15 inclusive, the referred to ports and grooves are clearly indicated and said sections represent the relationship of the ports and recesses or grooves with respect to the passages to the pressure fluid motors and to the main control valve and the time delay valve for one speed setting of the selector valve. It will be clear to one skilled in the art the manner in which the ports, passages and recesses or grooves cooperate for the other selector valve settings for the various speeds of the spindle.

Referring to Figs. 9 and 18a, it will be seen that the pipe I5I which is the inlet is connected to the bore I94 of the selector valve body through a drilled opening I formed in the rear end plate of the valve body.

Although the connections between the speed selector valve and the various pressure fluid motors for shifting the gear cones have been indicated diagrammatically by dash lines in Fig. and reference numerals applied to said lines, such connections will now be described in specific detail with reference to Figs. 9 to 15 inclusive, 10a. 12a, and 13a and the component parts of said connections will be given independent identifying reference numerals.

Referring to Figs. 9, 10 and 10a, it will be seen that the valve body IOI is provided with six radial ports and six lateral extensions from the circular peripheral groove 20I. The peripheral groove 20I overlies and communicates with a groove 202 formed in the underside of the valve housing plate and in turn communicating with a drilled opening 203 in the casting and leading to the drain or sump.

In the position of the valve shown in Figs. 9 and 10 the radial port 204 of the six radial ports is in communication with the drilled opening and groove 205 in the valve housing and which communicates with a drilled opening 206 in the housing of the pressure fluid motor 95, with said opening extending to one end of the cylinder of said motor. The lateral extension 201 of the six lateral extensions from the annular groove 20I communicates in this position of the valve with a drilled opening and groove 208 formed in the valve housing and communicating in turn with the drilled opening 209 in the housing of the pressure fluid motor 95 and extending to the opposite end of the cylinder of said motor.

Referring t Figs. 9, 10a and 11 it will be seen that the portion of the valve included in the section of Fig. 11 contains six radial ports and six lateral extensions from th circular groove 20I. In this position of the valve the lateral extension 2I0 registers with the drilled opening and groove 2 in the valve housing with said groove communicating with the drilled opening 2I2 formed in the housing of the pressure fluid motor 94 and communicating with one end of the cylinder thereof. The radial port 2 l3 communicates with the drilled opening and groove 2 in the valve housing with said groove communicating with the drilled opening 2l5 in the housing of the pressure fluid motor 94 and extending to the opposite end of the cylinder of said motor.

Referring to Figs. 9, l2 and 12a it will be seen that this portion of the valve contains eight radial ports and four lateral extensions from a circular peripheral groove US that overlies an opening and groove 2|! in the valve housing which communicates with a drilled opening 2" that leads to the sump. The lateral extension 2l9 of the four extensions communicates with a drilled opening and groove 229 in the valve housing and extending to the drilled opening 22! in the housing of the pressure fluid motor 98 and which latter opening communicates with one end of the narrow portion of the cylinder of said motor. The radial port 222 of the eight radial ports communicates with the drilled opening and groove 223 in the valve housing and the latter in turn with the drilled opening 224 in the housing of the motor 96 and extending to the opposite end of the cylinder of said motor.

Referring to Figs. 9, 13 and 13a it will be seen that this portion of the valve body is provided with four radial ports and eight lateral extensions from the annular groove 225. The annular groove 225 overlies a drilled opening and groove 226 in the valve housing which extends to an opening 221 in the casting and communicating with the sump. The radial port 228 in this position of the valve communicates with a drilled opening and groove 229 in the valve housing and extending to the drilled opening 239 in the housing of the motor 96 and communicating with the cylinder thereof intermediate its ends and at the end of the small bore portion of the cylinder immediately adjacent the large bore portion thereof, it being recalled that the motor 96 actuates the three step gear cone and hence must have three operative positions as will later become apparent.

Referring to Figs. 9, 14 and 15 it will be seen that the periphery of the valve body IIH at this portion thereof is Provided with a flat 23l extending axially of the body and forming with the wall of the valve chamber an axially extending passageway which when the body is turned and the flat overlies the drilled opemngs and grooves 232 and 233 will bridge said openings and place the same in communication with each other. The drilled opening and groove 232 communicates with a drilled opening 234 in the housing of the motor 96 with the latter communicating with a drilled opening 235 in the cylinder head 235 of the motor 96. The drilled opening and groove 233 communicates with a drilled opening 23! formed in the housing of the motor 96 and communicates in turn with a drilled opening 238 in the cylinder head 235.

The drilled opening 235 (see Fig. 20, Sheet 1) communicates with a drilled opening 239 extending at right angles thereto and formed in the cylinder head 236 and in the housing of the motor 96 and connected to the pipe I53. It will be noted that the openings 238 and 239 communicate with the bore for the piston rod 93, said openings being spaced 90 apart for a purpose later to be explained. The pipe I52 is connected to the top of an opening 240 formed in the plate I93 and in the housing for the motor 14 99. This opening 249 extends to the bore for the piston rod 88.

The housing for the motors 94, 98 and 95 is provided with an L-shaped opening or passage 2 intersecting the bores for the piston rods 88 and 89, see Figs. 18a and 20. The opening 24! extends to and communicates with an opening 242 formed in the housing of the motor 99 and communicating in turn with a drilled opening 243 which extends to the bore for the piston rod 93 and is aligned with the opening 288. The piston rods 86 and 88 of the motors 94 and 95 which shift the two two-step gear cones are provided with longitudinally spaced circumferential grooves 244 and 245 for the rod 86 and 249 and 241 for the rod 89. It will be seen that at the end of each operative stroke of the pistons 91 and 98 of the motors 94 and 95 one or the other of the grooves 244, 245; 246 and 241 will align with the opening or passage 24l and hence pressure fluid will be free to flow through said openings and past the piston rods and into the openings 242 and 248. The piston rod 98 of the three-position motor 96 is provided with longitudinally spaced L-shaped passages 248 and 249 and intermediate said L-shaped passages with a diametral passage 250, see Figs. 18a and 20.

It will be seen that when the piston 99 is in its most right hand position the L-shaped passage 249 in the piston rod 93 will register with the openings 243 and 239. When the piston 99 is in its intermediate position the diametral passage 259 will register with the openings 243 and 238, while when the piston 99 is in its most left hand position the L-shaped passage 248 will be in alignment with the openings 243 and 239.

The piston rod 93 of the motor 96 has slidably mounted thereon within the motor cylinder 8. stop piston 25l in the form of a headed sleeve with the head sliding in the large portion of the cylinder.

Referring to Fig. 180, the piston 99 is shown in its most right hand position. Assuming that it is desired to move the piston 99 to its intermediate position and that pressure fluid is flowing into the cylinder to the right of the piston and to the left of the stop piston, it will be seen that the stop piston will be moved to the limit of its right hand movement and that as soon as the piston 99 in its'leftward movement engages the right hand end of the sleeve of the stop piston further movement of the piston 99 toward the left will be arrested due to the area differentials between the piston 99 and the head of the stop piston 25l. This condition is clearly illustrated in Fig. 24.

When it is desired to move the piston 99 to its most left hand position, as indicaated in Fig. 25, then pressure fluid is admitted to the right of the piston 99 and the stop piston 25! and is exhausted from the left of the stop piston, whereupon the piston and the stop piston move as a unit toward the left until they have reached the left hand limit of movement. When it is desired to move the piston 99 to its intermediate or to its right hand position from its most left hand position, pressure fluid is admitted to the left of the stop piston and to the left of the piston 99, whereupon both pistons move toward the right until the stop piston reaches its most right hand position as indicated in Fig. 24. If pressure fluid continues to be supplied to the left of the piston 99 then said piston and piston rod will move toward the right relative to the stop piston from the position shown iii Fig. 24 and into the position shown in Fig. 23.

In order to coordinate and clarify the description hereinbefore given a rsum of the operation of the machine will now be set forth. Assuming that the sheave 33 and shaft 34 are being power driven and that the pump I28 is operating so that the pressure fluid system can function and that a work piece is mounted in the chuck of the work spindle'while the control handle I23 is in positions 1 and N, that is normal and neutral positions, then the operator turns the wheel I04 to set the selector valve I for the desired spindle speed in relation to the diameter of the work in accordance with the cutting speed in feet per minute of the tool. 01 course the operator could have near the end of the previous work cycle turned the wheel I04 to set the selector valve I00 to preselect the spindle speed for the new operative cycle. It will be assumed that the spindle speed selected corresponds to the setting of the valve I00 as shown in Figs. 9 to inclusive. Inasmuch as the control handle is in positions 1 and N the settings of the selector valve does not cause the gears to be shifted since said valve is receiving no pressure fluid at this time. The operator by moving the control lever inwardly from position 1 to position 3 shifts the gear shifting cycle control valve body II9 from the position shown in Fig. 5 into the position shown in Fig. 18 and the spring detent I26 will hold the valve body H9 in its shifted position. The shifting of the valve body II9 initiates the gear shifting cycle since it causes the pressure fluid to flow via the main control valve from supply groove I33 into the groove I35 and then through groove I35 and pipe I38 to the motor 63 which contracts the brake band 59 to hold the internal gear 50 stationary and cause. through the planetary unit a crawl speed to be imparted to the gear 64 and to the change speed transmission in the forward direction. Also at this time the groove I36 is connected through the groove I35 to the pipe I31 which extends to the time delay unit II3 of the time delay valve. After the time interval has elapsed that is required for the pressure fluid to flow through the unit H3 and build up in the valve chamber to the right of said unit, said fluid operates on the shiftable time delay valve body to shift the same toward the right from the position shown in Figs. 4 and 8 and into the position shown in Fig. 18; At this time the pressure fluid is flowing to the time delay valve through the pipe I34 which is connected with the passages I85 and I88 in the time delay valve. It will be noted that the pressure fluid flows to the right of the time delay valve through the passage I85 but due to the area difierentials of the opposite ends of said valve body the latter is maintained against this pressure in its right hand position. The pressure fluid flowing through passage I88 passes between the lands I82 and I83 of the time delay valve and outwardly through the pipe I 5I to the interior of the selector valve body IOI. Also the pressure fluid passing between the lands I82 and I83 flows through the passage I 9| and pipe I52 to the opening 240.

It will be noted that the pressure fluid flows first through conduit pipe into the selector valve before it flows through pipe I52 to the opening 240. Hence the pistons of the motors 94, 95 and 96 will start moving before the pressure fluid is in the opening 240 and thus by the time 16 that the pressure fluid is in said opening the piston rods of said motors will have moved to fill the bore and block the opening I.

It will be seen that at least one of the three piston rods must move to effect a gear shift and hence the passage of fluid through openings 24I, 243 and 239 will always be blocked untilthe shifting has been completed. As soon as the pistons of the motors have been shifted to produce the selected gear shift then the annular grooves in the piston rods 86 and 88 and either the L-shaped passages 248 and 249 or the straight passage 250 in the piston rod 93 will open the openings 2M, 242 and 243 so pressure fluid can flow through the opening 239 and thence by the. pipe I63 to the annular groove I92 in the housing of the time delay valve, from whence it goes to the pipe I50 and thence through grooves I48 and I49 and into the right hand end of the valve chamber of the main control valve to shift the slidable valve body 9 from its right hand position of Fig. 18 into its left hand position of Fig. 5. The shifting movement overcomes the detent I26 to take it out of the left hand groove in the extension of the slidable valve body until it snaps into the right hand groove to hold the valve body in its left hand position. Also the shifting of the valve body H9 assures that the control lever I23 is returned to position I. At this time the pressure fluid is passing from the inlet port I1I between the lands I11 and I19 of the shiftable valve body and thence into passages I12 and I13 of the rockable valve body IIB, the passage I12 being connected to the port I14 and the pressure fluid is returning to the sump.

It will be understood that as soon as the shiftable valve body II9 has been shifted from its right hand position back to its normal left hand position of Fig. 5 then the land I11 located between the ports I10 and Ill interrupts the flow of pressure fluid to the groove I36 and thence through the groove I35 and pipe I31 to the time delay valve. Also at this time the wide land I18 of the valve body II9 has moved to the left of the radial passages I15 and hence the pressure fluid in the time delay valve to the right of the time delay unit can drain to the sump through the passage I8I and pipe I64. This removes the pressure from the left hand end of the time delay valve body and hence the fluid pressure which is continuously exerted on the right hand end of this valve body shifts the same toward the left from the position shown in Fig. 18 into the position shown in Figs. 4 and 8. As soon as the body of the time delay valve has moved to its normal left hand position the wide land I83 clears'the port I92 and hence the pressure fluid in the pipe I83 can drain through the port I89 while similarly the pressure fluid to the right of the shiftable valve body I I9 and in the groove I49 and pipe I50 can drain through the ports I88 and I89.

Assuming that the operator desires to have the spindle rotate in the forward direction at the selected speed he now moves the control handle outwardly from position 1 to position 2 to clear the lugs I22a with respect to the lug I2Ib, it being recalled that at this t me the spring pressed plunger I24 is compressed. The operator can now shift the control handle laterally to the left from position N to position F to rock the valve body II 8 and bring the passage I12 into communication with the groove I46 from whence the pressure fluid will fiow through the groove I40 and pipe I" to the main clutch and cause said clutch to be engaged, whereupon the transmission and the spindle will be driven in the forward direction at the selected or preselected speed. As soon as the operator releases the control handle while in forward position the plunger I24 moves the control handle inwardly from position II to position I, thus causing the right hand lug I22a to lie to the left of the lug I2Ib, wherefore the control handle cannot be moved to neutral position until it is rocked outwardly from position I to position II.

Assuming that the operative step has been completed and the operator wishes to stop the rotation of the spindle and the change speed transmission he pulls the control handle outwardly from position I to position II to free the stop lugs and then rocks the control lever laterally from position F to position B, whereupon the passage I13 in the rockable valve body IIB will align with the groove I40 while the passage I12 will move out of alignment with the groove I46 and will be dead-ended and said groove I46 will be connected to the drain port I14. Hence groove I40 is now receiving pressure fluid which flows to groove I 39 and pipe MI and thence to the motor 6i which actuates the brake drum to brake the rotation of the gear 64 and the rotation of the transmission and spindle, it being noted that at this time the main clutch is disengaged. After the braking of the transmission and spindle the operator would move the control handle laterally to neutral position whereupon the passage II3 is dead-ended and the passage I12 is connected to drain. Also at this time the fluid in the pipe to the brake motor GI is draining.

Assuming that the second operative step in the its right hand position of Fig. 18 whereupon the crawl speed is initiated as previously explained and pressure fluid flows through the time delay valve to the selector valve and the gear cones are shifted to the selected speed, after which the valve body N9, the control handle I23 and the time delay valve III will be returned automatically to their normal positions by fluid pressure. The operator then moves the control handle I23 outwardly from position I to position II, after which he swings the handle laterally from position N to position R to rock the valve body II8, whereupon the passage H2 in said rockable valve body will be connected with the groove I43 and through groove I42 with pipe I44 that extends to the motor 62 which actuates the brake drum 58 of the planetary unit to cause reverse rotation to be imparted to the transmission and the spindle. It will be understood that the control handle will be retained in position R when the operator releases his hold thereon by the left hand lug I 22a lying to the right of the lug I 22b and it will also be understood that the handle, due to the spring-pressed plunger I24, moves from position II to position I. It will be understood that at the end of the second operative step the operator again moves the control handle I23 outwardly from position I to position H and thence laterally to the left from position It to position B to brake the rotation of the transmission and spindle and thence into neutral position. 5 The second operative step in the cycle has been described as a left hand threading operation at a lower speed than the first step. It should be noted that had the second operative step required a diiferent speed than the first operative step but still in the forward direction then the operator would not need to move the control handle out of position F (forward) in order to obtain the new spindle speed in the forward direction required for the second operative step. In such case the operator during the first operative step could set the speed selector valve by rotating the hand wheel I04 to preselect the desired spindle speed for the second step. Then upon completion of the first step while the spindle is still rotating at the speed required for the first step the operator need merely move the control handle while in position F inwardly from position I to position III to shift the gear shifting cycle control valve body H9 from its normal left hand position to its right hand position to initiate the gear shifting cycle. As soon as the valve body H9 has been so shifted the main clutch is automaticallydisengaged, the speed of the transmission and spindle is reduced by the braking action of the crawl speed brake band of the planetary unit until the transmission is rotating in the crawl speed. During this time pressure fiuid has flowed through the time delay unit, shifted the time delay valve body to the right and then flowed to the speed selector valve so that when the motors 94, 95 and 00 function to shift the gear cones to obtain the preselected speed the transmission is already in crawl speed and hence the shifting is facilitated. As soon as theshifting has been completed and not prior thereto the cycle valve body H9 is returned to its normal most left hand position whereupon the main clutch is engaged, the time delay valve body is returned to its normal position and the spindle commences rotation in the forward direction at the new speed. A selected or preselected spindle speed can be obtained in a similar manner when the control handle is in brake or reverse positions without necessitating the movement of the control handle from such positions to neutral position.

It will be understood that in the two cases Just mentioned as soon as the gear shifting has been completed the transmission will be restored to 55 brake or reverse as the case might be.

From the foregoing explanation of the modes of operation of the mechanism it will be seen that once the gear shifting cycle has been initiated by the manual inward movement of the control handle then said cycle is carried out auto- I matically and at the end thereof the valve body I I9 is restored to its normal position.

Although a preferred embodiment of the invention has been illustrated anddescribed herein it will be understood that the invention is susceptible of various adaptations and modifications within the scope of the appended claims.

Having thus described my invention, I claim: 1. In a machine tool having a movable part, 7 a transmission for moving said part at different speedsand including shiftable elements, individual pressure fluid motors for shifting said elements, and means for actuating said motors in predetermined manner and including a pressure 7 fluid source, a pressure fluid circuit from said '1 source to said motors and having therein a settable speed selector valve and a speed changing cycle valve movable from a normal position wherein said circuit to said selector valve and motors is interrupted to a cycle initiating position to cause pressure fluid to flow to said select or valve and said motors to effect predetermined shifting of said elements, said circuit including means functioning automatically upon the completion of the speed changing cycle to restore said cycle valve to its normal position.

2. In a machine tool having a movable part, a transmission for moving said part at different speeds and including shiftable elements, a power source, clutch means between said source and said transmission, a pressure fluid motor for actuating said clutch, individual pressure fluid motors for shifting said elements, and means for actuating said motors in predetermined manner and including a pressure fluid source, a pressure fluid circuit from said pressure fluid source to said motors and having therein a settable speed selector valve and a speed changing cycle valve movable from a normal position wherein said clutch motor receives pressure fluid and said clutch is engaged while said circuit to said individual motors and said selector valve is interrupted to a cycle initiating position to interrupt flow of pressure fluid to said clutch motor to effect disengagement of said clutch and to cause pressure fluid to flow to said selector valve and said individual motors to efl'ect element shifting, said circuit including means functioning automatically upon the completion of the speed changing cycle to restore said cycle valve to its normal position.

3. In a machine tool as defined in claim 2 and wherein said pressure fluid circuit includes a time delay valve intermediate said cycle valve and said speed selector valve and acting to cause the interposition of a time delay between the disengagement of the clutch and the flow 01' pressure fluid to said selector valve and said individual motors.

4. In a machine tool having a movable part, a transmission for moving said part at diflferent speeds and including shlftable elements, means for imparting a slow nonworking speed to said transmission, a pressure fluid motor for actuating said means, individual pressure fluid motors for shifting said elements and means for actuatin said motors in predetermined manner and including a pressure fluid source, a pressure fluid circuit from said source to said motors and having therein a shiftable speed selector valve and a speed changing cycle valve movable from a normal position wherein the flow of pressure fluid to said motors and said selector valve is interrupted and hence said slow nonworking speed means and said individual motors are inactive to a cycle initiating position wherein pressure fluid flows to said slow nonworking speed motor, then said selector valve and then said individual motors to cause initiation of said slow nonworking speed and then the actuation of said individual motors to shift said elements, said circuit including means functioning automatically upon the completion of the speed changing cycle to restore said cycle valve to its normal position to render said slow nonworking speed means inactive and interrupt the flow of pressure fluid to said individual motors and said selector valve.

5. In a machine tool as defined in claim 4 and wherein said pressure fluid circuit includes a time delay valve intermediate said cycle valve and said 20 speed selector valve and acting to cause the interposition of a time delay between the initiation of the slow nonworking "speed and the flow of pressure fluid to said selector valve and said individual motors.

6. In a machine tool having a movable par a transmission for moving said part at different speeds and including shiftable elements, a power source, clutch means between said power source and said transmission, a pressure fluid motor for actuating said clutch, individual pressure fluid motors for shifting said elements, means for imparting a slow nonworking speed-to said transmission when said clutch is disengaged. a Dr sure fluid motor for actuating said last means, and means for actuating said motors in predetermined manner and including a pressure fluid source, a pressure fluid circuit from said source to said motors and having therein a settable speed selector valve and a speed changing cycle valve movable from a normal position wherein said clutch motor receives pressure fluid and said clutch is engaged while the flow of pressure fluid to said individual motors and said selector valve and to said nonworking speed motor is interrupted and hence said clutch is engaged and said nonworking speed means and said individual motors are inactive to a cycle initiating position wherein ressure fluid is interrupted to said clutch motor but flows to said nonworking speed motor and then to said selector valve and said individual motors to cause disengagement of said clutch, initiation of said nonworking speed and the actuation of said individual motors to shift said elements, said circuit including means functioning automatically upon the completion of the speed changing cycle to restore said cycle valve to its normal position to render said nonworking speed means inactive, engage said clutch and interrupt the flow of pressure fluid to said individual motors and said selector valve.

7. In a machine tool as defined in claim 6 and wherein said pressure fluid circuit includes a time delay valve intermediate said cycle valve and said speed selector valve and acting to cause the interpositon of a time delay between the disengagement of the clutch, the initiation of the nonworking speed and the flow of pressure fluid to said selector valve and said individual motors to eifect shifting of said elements.

8. In a machine tool having amovable part, a transmission for moving said part at different speeds and including shiitable elements, a power source for driving said transmission and including forward and reverse clutch means, pressure fluid motors for actuating said clutch means, individual pressure fluid motors for shifting said elements, and means for actuating said motors in predetermined manner and including a pressure fluid source, a pressure fluid circuit from said pressure fluid source to said motors and having therein a settable speed selector valve and a speed changing cycle valve movable from a normal position wherein one or the other of said clutch motors receives pressure fluid and one or the other of said forward or reverse clutch means is engaged but said circuit to said individual motors and said selector valve is interrupted to a cycle initiating position to interrupt flow of pressure fluid to said clutch motors to eifect disengagement of either said forward clutch means or said reverse clutch means and to cause pressure fluid to flow to said selector valve and said individual motors to effect element shifting, said circuit including means functioning automati- 21 cally upon the completion of the speed changing cycle to restore said cycle valve to its normal position, said circuit further including a direction control valve settable to selectively control the actuation of said clutch motors when said cycle valve is in normal position.

9. A machine tool as deflned in claim 8 and wherein said pressure fluid circuit includes a time delay valve intermediate said cycle valve and said speed selector valve and acting to cause the interposition of a time delay between the disengagement of the clutch means and the flow of pressure fluid to said selector valve and said individual motors.

10. In a machine tool having a movable part, a transmission for moving said part at diflerent speeds and including shiftable elements, a power source for driving said transmission and including forward and reverse'clutch means, pressure fluid motors for actuating said clutch means, means for imparting to said transmission a slow nonworking speed drive, a pressure fluid motor for actuating said last means, individual pressure fluid motors for shifting said elements, and

means for actuating said motors in predetermined manner and including a pressure fluid source, a pressure fluid circuit from said pressure fluid source to said motors and having therein a settable speed selector valve and a speed changing cycle valve movable from a normal position wherein one or the other of said clutch motors receives pressure fluid and one or the other of said forward or reverse clutch means is engaged while said circuit to said nonworking speed motor and said individual motors and said selector valve is interrupted to a cycle initiating position to interrupt flow of pressure fluid to said clutch motors to effect disengagement of either said forward clutch means or said reverse'clutch means and to cause pressure fluid to flow to said nonworking speed motor, then to said selector valve and then to said individual motors to effect flrst the slow nonworking speed drive of the transmission and then shifting of the shiftable elements to change the speed of said part, said circuit including means functioning automatically upon the completion of the speed changing cycle to restore said cycle valve to its normal position, said circuit further including a direction control valve settable to selectively control the actuation of said clutch motors when said cycle valve is in normal position.

11. In a machine tool as defined in claim 10 and wherein said pressure fluid circuit includes a time delay valve intermediate said cycle valve and said speed selector valve and acting to cause the interposition of a time delay between the disengagement of the clutch and the initiation of the nonworking speed and the flow of pressure fluid to said selector valve and said individual motors to eiiect shifting of said elements.

12. In a machine tool having a movable part, a transmission for moving said part at different speeds and including shiftable elements, braking means for said transmission, a pressure fluid motor for actuating said braking means, individual pressure fluid motors for shifting said elements and means for actuating said motors in predetermined manner and including a pressure fluid source, a pressure fluid circuit from said source to said motors and having therein a settable speed selector valve and a speed changing cycle valve movable from a normal position wherein said braking means motor may receive pressure fluid to brake the transmission but said 22 circuit to said selector valve and said individual motors is interrupted to a cycle initiating position to interrupt flow of pressure fluid to said .braking means motor to eifect release of the brake and to cause pressure fluid to flow to said selector valve and said individual motors to eflect element shifting, said circuit including means functioning automatically upon the completion of the speed changing cycle to restore said cycle valve to its normal position.

13. A machine tool as defined in claim 12 and wherein said circuit further includes a braking means control valve in series with said cycle valve and acting when said cycle valve is in normal position to selectively control the actuation of said braking means motor to apply and release said braking means.

14. In a machine tool having a movable part, a transmission for moving said part at diflerent speeds and including shiftable elements, braking means for said transmission, a pressure fluid motor for actuating said braking means, means for imparting a slow nonworking drive to said transmission, a pressure fluid motor for actuating said last means, individual pressure fluid motors for shifting said elements, and means for actuating said motors in predetermined manner and including a pressure fluid source, a pressure fluid circuit from said source to said motors and having therein a settable speed selector valve and a speed changing cycle valve movable from a normal position wherein pressure fluid may flow to said braking means motor but is interrupted to said slow nonworking speed motor, said selector valve and said individual motors to a cycle initiating position to interrupt flow of pressure fluids to said braking means motor to efl'ect release of the braking means and to cause pressure fluid to flow to said nonworking speed motor to initiate the slow drive of the transmission and to said selector valve and said individual motors to effect element shifting, said circuit including means functioning automatically upon the completion of the speed changing cycle to restore said cycle valve to its normal position at which time the braking means may be actuated while pressure fluid flow to said nonworking speed motor, said selector valve and said individual motors is interrupted.

15. A machine tool as defined in claim 14 and wherein said pressure fluid circuit includes a time delay valv intermediate said cycle valve and said speed selector valve and acting to cause the interposition of a time delay between the release of the braking means and the initiation of the slow nonworking speed and the flow of pressure fluid to said selector valve and said individual motors to effect shifting of said elements.

16. In a machine tool having a movable part, a transmission for moving said part at different speeds and including shiftable elements, a power source for driving said transmission and including forward and reverse clutch means, pressure fluid motors for actuating said clutch means, brake means for braking said transmission, a fluid pressure motor for actuating said braking means, individual pressure fluid motors for shifting said elements, and means for actuating said motors in predetermined manner and including a pressure fluid source, a pressure fluid cir cuit from said pressure fluid source to said motor and having therein a settable speed selector valve and a speed changing cycle valve movable from a normal position wherein one or the other of said clutch motors may receive pressure fluid 

